<?php

/**
 * Simple filter to handle matching of boolean values
 *
 * Definition items:
 * - label: (REQUIRED) The label for the checkbox.
 * - type: For basic 'true false' types, an item can specify the following:
 *    - true-false: True/false (this is the default)
 *    - yes-no: Yes/No
 *    - on-off: On/Off
 * - accept null: Treat a NULL value as false.
 */
class views_handler_filter_boolean_operator extends views_handler_filter {

    // exposed filter options
    var $no_single = TRUE;
    // Don't display empty space where the operator would be.
    var $no_operator = TRUE;
    // Whether to accept NULL as a false value or not
    var $accept_null = FALSE;

    function construct() {
        $this->value_value = t('True');
        if (isset($this->definition['label'])) {
            $this->value_value = $this->definition['label'];
        }
        if (isset($this->definition['accept null'])) {
            $this->accept_null = (bool) $this->definition['accept null'];
        } else if (isset($this->definition['accept_null'])) {
            $this->accept_null = (bool) $this->definition['accept_null'];
        }
        $this->value_options = NULL;
        parent::construct();
    }

    /**
     * Return the possible options for this filter.
     *
     * Child classes should override this function to set the possible values
     * for the filter.  Since this is a boolean filter, the array should have
     * two possible keys: 1 for "True" and 0 for "False", although the labels
     * can be whatever makes sense for the filter.  These values are used for
     * configuring the filter, when the filter is exposed, and in the admin
     * summary of the filter.  Normally, this should be static data, but if it's
     * dynamic for some reason, child classes should use a guard to reduce
     * database hits as much as possible.
     */
    function get_value_options() {
        if (isset($this->definition['type'])) {
            if ($this->definition['type'] == 'yes-no') {
                $this->value_options = array(1 => t('Yes'), 0 => t('No'));
            }
            if ($this->definition['type'] == 'on-off') {
                $this->value_options = array(1 => t('On'), 0 => t('Off'));
            }
        }

        // Provide a fallback if the above didn't set anything.
        if (!isset($this->value_options)) {
            $this->value_options = array(1 => t('True'), 0 => t('False'));
        }
    }

    function option_definition() {
        $options = parent::option_definition();

        $options['value']['default'] = FALSE;

        return $options;
    }

    function operator_form(&$form, &$form_state) {
        $form['operator'] = array();
    }

    function value_form(&$form, &$form_state) {
        if (empty($this->value_options)) {
            // Initialize the array of possible values for this filter.
            $this->get_value_options();
        }
        if (!empty($form_state['exposed'])) {
            // Exposed filter: use a select box to save space.
            $filter_form_type = 'select';
        } else {
            // Configuring a filter: use radios for clarity.
            $filter_form_type = 'radios';
        }
        $form['value'] = array(
            '#type' => $filter_form_type,
            '#title' => $this->value_value,
            '#options' => $this->value_options,
            '#default_value' => $this->value,
        );
        if (!empty($this->options['exposed'])) {
            $identifier = $this->options['expose']['identifier'];
            if (!isset($form_state['input'][$identifier])) {
                $form_state['input'][$identifier] = $this->value;
            }
            // If we're configuring an exposed filter, add an <Any> option.
            if (empty($form_state['exposed']) || !empty($this->options['optional'])) {
                $any_label = variable_get('views_exposed_filter_any_label', 'old_any') == 'old_any' ? '<Any>' : t('- Any -');
                if ($form['value']['#type'] != 'select') {
                    $any_label = check_plain($any_label);
                }
                $form['value']['#options'] = array('All' => $any_label) + $form['value']['#options'];
            }
        }
    }

    function value_validate(&$form, &$form_state) {
        if ($form_state['values']['options']['value'] == 'All' && empty($form_state['values']['options']['expose']['optional'])) {
            form_set_error('value', t('You must select a value unless this is an optional exposed filter.'));
        }
    }

    function admin_summary() {
        if (!empty($this->options['exposed'])) {
            return t('exposed');
        }
        if (empty($this->value_options)) {
            $this->get_value_options();
        }
        // Now that we have the valid options for this filter, just return the
        // human-readable label based on the current value.  The value_options
        // array is keyed with either 0 or 1, so if the current value is not
        // empty, use the label for 1, and if it's empty, use the label for 0.
        return $this->value_options[!empty($this->value)];
    }

    function expose_options() {
        parent::expose_options();
        $this->options['expose']['operator'] = '';
        $this->options['expose']['label'] = $this->value_value;
        $this->options['expose']['optional'] = FALSE;
    }

    function query() {
        $this->ensure_my_table();

        $where = "$this->table_alias.$this->real_field ";

        if (empty($this->value)) {
            $where .= '= 0';
            if ($this->accept_null) {
                $where = '(' . $where . " OR $this->table_alias.$this->real_field IS NULL)";
            }
        } else {
            if (!empty($this->definition['use equal'])) {
                $where .= '= 1';
            } else {
                $where .= '<> 0';
            }
        }
        $this->query->add_where($this->options['group'], $where);
    }

}
